Seeking compensation in the Victorian Civil and Administrative Tribunal, she said her final secondary school score was too low to study law at the University of Sydney.

Of her time at Geelong Grammar, she said: ''I didn't ever feel I was getting the support I needed to really excel.''

Ms Ashton-Weir boarded at the school in 2008 and 2009 but finished her secondary studies at a TAFE college in Sydney. She is in the first year of a double degree in arts and sciences at the University of Sydney.

Her mother, Elizabeth Weir, is also suing the school for lost income and other expenses.

She said she gave up her chocolate fortune cookie business - which she had expected to make A$450,000 (NZ$583,681) over three years - because her daughter moved from Geelong to live with her in New South Wales.

She is also seeking compensation for A$39,000 (NZ$50,575) in rent paid when they moved to another house in Sydney.

Earlier this week, Ms Weir said the school had known her daughter was gifted and had scored highly in an intelligence test, but struggled in maths.

Yesterday, Ms Ashton-Weir told the tribunal a teacher at Geelong Grammar had criticised her for using words that were too long, which had left her confused and had made her doubt her ability to write essays. She became ''quite distressed'' when her English marks began to fall.

Darren Ferrari, representing Geelong Grammar, said Ms Ashton-Weir could have studied law at several other universities. ''You could have done law at Deakin University by correspondence,'' he said.

He said Ms Ashton-Weir had been placed on ''internal suspension'' a number of times while at the school. She was also poorly organised and had been absent from class many times.

Ms Ashton-Weir fell ill with glandular fever in early 2009 and went to stay with her mother at the end of term two. She did not return to Geelong Grammar.

Mr Ferrari said the school had tried to support Ms Ashton-Weir. ''The school wanted her to get through the year.''

He said Ms Ashton-Weir's school reports noted she was intelligent but failed to complete school work.